Vehicle design related to aerodynamics includes factors affecting vehicle drag, wind noise, vehicle noise emissions, and lift forces that affect traction, cornering and other elements of vehicle stability. Aerodynamic design elements may include passive elements and actively controlled elements. Knowledge of the aerodynamic forces acting on the vehicle are required for precise control of an active aerodynamic system. Known aerodynamic systems are not actively controlled in response to downforce estimations associated with operation of the vehicle.